Crime Classification Manual Part I 1

A STANDARD SYSTEM FOR INVESTIGATING AND CLASSIFYING VIOLENT CRIMES

SECOND EDITION

 

John E. Douglas, Ann W. Burgess, Allen G. Burgess, and Robert K. Ressler,

Editors

                                  PART ONE                                 

 

Crime Analysis and Investigation

 

CHAPTER 1

Modus Operandi and the Signature Aspects of Violent Crime

JOHN E. DOUGLAS LAUREN K. DOUGLAS

In September 1989, a Shreveport, Louisiana, man named Nathaniel Code Jr. stood trial for murder. The jury determined Code had mur- dered eight people between 1984 and 1987. These eight homicides took place during three different events: one murder in 1984, four in 1985, and three in 1987. There were several disparities in modus operandi (actions taken by an offender during the perpetration of a crime in order to perpetrate that crime) and victimology (characteristics of the victims) among the three crime scenes.

Could one man be linked to the murders at all three scenes? With differ- ences in modus operandi (MO) and victimology, what could link Code with each of these eight homicides? MO and victimology are important factors in an investigation, but they are often somewhat generalized and offer less about the subtle details about personality and, ultimately, identity that are of- ten necessary to track down an offender. However, personation, that is, the offender’s signature, or his “calling card,” is an individualized set of indica- tors that can point specifically to an offender’s personality. (See Chapter Two for more information on personation.) In the case of multiple crimes com- mitted by the same (or serial) offender, there is often repeated personation. This was true in the case of Nathaniel Code. He left his signature—gags, duct tape, and bodies with gunshot wounds and slashed throats—at each of the three crime scenes. This linked Code with all eight murders.

No one in contemporary law enforcement would dispute that our society has far too many Nathaniel Codes. The increase of violent crime has com- pelled law enforcement to develop new measures to address it. One important step is the recognition of the serial offender who often crosses jurisdictional boundaries. Any effective effort among local, state, and federal agencies depends on early recognition of a serial offender as such; different jurisdic- tions looking for the same offender need to recognize that they are after the same person and cooperate with one another. But the common crossing of multiple jurisdictional lines by offenders makes this a great challenge. Comprehensive analysis of victimology, crime scene, and forensics, as well as the careful interview and examination of any living victims to gather information about the offender’s verbal and nonverbal behavior, can help an agency discover a serial offender within its own jurisdiction or among sev- eral others.

The MO has great significance when investigators attempt to link cases.

An appropriate step of crime analysis and correlation is to connect cases due to similarities in MO. However, an investigator who rejects an offense as the work of a serial offender solely on the basis of disparities in MO (as in the Code cases) has made a mistake. What causes an offender to use a certain MO? What influences shape it? Is it static or dynamic? The answers to these questions help investigators avoid the error of attributing too much signifi- cance to MO when linking crimes.